Department of Orthodontics, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
Am J Orthod Dentofacial Orthop. 2013 Apr;143(4 Suppl):S85-91. doi: 10.1016/j.ajodo.2012.09.009.
There has been continuing interest in the development and use of esthetic and effective orthodontic archwires. The aims of this study were to evaluate the inner alloy core dimensions of 4 brands of as-received esthetic coated wires and their mechanical properties before and after 21 days of oral exposure, compared with conventional stainless steel and nickel titanium wires.
Four groups (Ortho Organizers, Carlsbad, Calif; TP Orthodontics, LaPorte, Ind; Orthometric, Beijing, China; and Trianeiro, Rio Claro, São Paulo, Brazil) of orthodontic archwires were tested. Five properties were evaluated: inner wire dimensions, modulus of elasticity, modulus of resilience, maximum deflection force, and load deflection curve characteristics. Images of the transverse sections from the specimens were made with a stereoscope. The inner alloy core dimensions of each wire were measured by using Image Pro Plus software (version 4.5; Media Cybernetics, Silver Spring, Md). All specimens were tested in a universal testing machine in a 3-point bending test.
Coated wires of the Ortho Organizers and Trianeiro groups showed greater reductions in their inner alloy core dimensions and produced lower loading and unloading forces and lower modulus of elasticity, modulus of resilience, and maximum deflection force values than did their control wires. Inner alloy core dimensions and the mechanical behavior of coated wires practically did not differ from the control wires in the TP Orthodontics and Orthometric groups.
The reduction on the inner alloy core dimensions to compensate for the coating thickness seems to be the variable responsible for greater changes in the mechanical properties of esthetic coated wires.
人们一直关注美观且有效的正畸弓丝的开发和使用。本研究的目的是评估 4 种不同品牌的预涂层美观弓丝的内合金芯尺寸，并与传统不锈钢和镍钛弓丝比较它们在口腔暴露 21 天后的机械性能。
对 4 组正畸弓丝（Ortho Organizers，加利福尼亚州卡尔斯巴德；TP Orthodontics，印第安纳州拉波特；Orthometric，中国北京；Trianeiro，巴西圣保罗马里奥克拉罗）进行了测试。评估了 5 个性能：内芯尺寸、弹性模量、回弹性模量、最大挠度力和负载挠度曲线特征。使用立体显微镜对样本的横截面对进行了图像拍摄。使用 Image Pro Plus 软件（版本 4.5；马里兰州银泉市 Media Cybernetics）对每条弓丝的内芯合金尺寸进行测量。所有样本均在万能试验机上进行三点弯曲测试。
Ortho Organizers 和 Trianeiro 两组涂层弓丝的内芯合金尺寸减小幅度较大，其加载和卸载力较低，弹性模量、回弹性模量和最大挠度力值也较低。TP Orthodontics 和 Orthometric 两组的控丝与涂层丝的内芯合金尺寸和力学性能几乎没有差异。
内芯合金尺寸的减小以补偿涂层厚度似乎是导致美观涂层弓丝力学性能发生较大变化的变量。
